Process of making closure caps



April 1, 1947. w. J. KEITH PROCESS OF MAKING CLOSURE CAPS Filed Oct. l5, 1943 Patented Apr. l, 1947 William J. Keith, Brookline, Mass., assigner to Brookline, Mass., a corporation of Massachusetts Application October 13, 1943, Serial No. 506,096

Keith-Peabody, Inc.,

6 Claims.

This invention relates to a process of making improved closure caps of the characterused for closing and sealing containers, such as jars, bottles, cans and other such receptacles.

The object of this invention is to improve the construction of such closure caps, to enable them to be manufactured of paper or other non metallic material in a simple and effective manner, and yet providing the necessary strength and rigidity for practical use.

A further object of the invention is to improve the side wall structure of a closure cap, to enable it to be manufactured either of multiple shells drawn to proper shape, or of convolutely wound paper ribbon with a shell, and to form therein a thread groove of sufficient strength and rigidity for effectively securing the cap in sealed relation on the container.

These objects are accomplished in the preferred embodiment of the invention by shaping a paper shell of the desired size, forming a thread groove in the flange portion thereof, and then fitting another shell or shells, or a convolutely wound sleeve or cylinder, over the first shell and rolling a thread groove in the second shell or cylinder, so as to t into the first thread groove, whereby the side wall structure will be reenforced for requisite rigidity, and a` thread groove -will be formed also of substantial rigidity and strength eiiective for securing the cap on the container. This enables the cap to be manufactured with automatic machinery in a simple and expeditious manner, and although made of paper or such non-metallic material, it has the desired strength and rigidity eiective for the purpose. It may be decorated or illustrated with `any desired designs, trade-marks or the like, and where the inside of the cap is coated, the liner usually required may be entirely omitted.

The invention is illustrated in different embodiments in the accompanying drawings, in which: l

Fig. 1 is a cross section through a single paper shell initially formed;

Fig. 2 is a similar View showing the formation of a thread groove therein; i

Fig. 3 is a side elevation of the rst shell showing in section a second shell fitted thereover;

Fig. 4 is a cross section through the combined shells and interiitting thread grooves;

Fig. 5 is a similar view with a convolutely wound ribbon cylinder covering the first shell; l Fig. 6 is a cross section similar to Fig. 4, with a covering shell thereover;

Fig. 7 is a. similar view showing another forni` of decorative covering on the combined shells;

Fig. 8 is a similar view showing a surrounding convolutely wound ribbon thereon; and

Fig. 9 is a detail sectional view showing a further modification of the closure cap.

, This invention involves the formation of the closure cap from a plurality of paper shells or cylindrical structures which are fitted together, and separately formed to provide the required thread groove therein. l These may be formed individually `of single plies of paper, or each shell or cylindrical section may be made up of multiple plies, although the second shell or cylindrical section will be applied over the initial shellor section after the latter is completely formed.

I have shown in Fig. l, the first shell formed of paper or other non-metallic material. This shell may be formed from a single sheet, and drawn or shaped by dies to provide a top I with a surrounding wall 2 formed by an integral ilange on the top l. When formed with dies, thepaper may be shaped quickly and without objectionable wrinkles, enabling the caps to be formed at high speed on automatic machines and to be handled with a minimum of effort.

After thus forming the flange on the disc, a thread groove 3 is rolled into the side wall ange 2, so as to form a thread, or partial thread, of desired characteristics on the inner wall of the cap, by impressing this in the relatively thin material of the ange.

Thereafter, a second paper shell, designated generally by the numeral t, is tted over the .shell |-2. A shell 4 is similarly made of relatively thin paper drawn to cylindrical shape, as shown in Fig.

`3, and only slightly larger than the'shell l-Z to t. tightly thereover. The shell 4 may also be formed with dies, and being of relatively thin paper or the like, may be applied effectively to the ilrst shell. Either the first or the second shell may be coated on the abutting face with an adhesive suitable to secure the shells directly together, preferably throughout their contacting area, or air drying plastics or thermo-plastics may be u sed to bind the shells directly together, securingr positive stability with rigid top Vand side w'alls. Afterthus fitting the second shell l over the first shell, and before the adhesive or other securing material has set, a thread groove 5 is rolled or impressed into the first` thread groove 3, as shown in Fig.- 4, thus providing a multiple ply thread groove within the capthe partsofV which are adhesively or otherwise rigidly secured together. l Instead of` using a complete shell to t over the flrst shell, a cylindrical portion may be used, as shown in Fig. 5, where substantial end wall rigidity is not required. In this form, the cylindricalportion is designated generally at 6 surrounding the Wall flange 2. The cylindrical portion is formed preferably by a convolutely wound paper ribbon, as shown at I6 in Fig. 9, which is adhesively applied and Wound directly on the Wall` flange 2, of multiple convolutions of thin material to provide the desired strength in the side Wall of the cap. Such a convolutely Wound ribbon may be used upon a paper wall, although it is diicult to start the Winding of a paper ribbon convolutely upon a metal form, thus lending itself effectively to this method of construction.

After thus forming the cylindrical portion 6, a

thread groove 'I is rolled or impressed in complementary relation in the thread groove. 3.

After thus forming the shell structure of multiple plies of side walls, a finishing surface is provided, such as by means of a third shell 8, shown in Fig. 6, Which is then applied to the shells l--Z and 4. The shell 8 should be plain Without thread in the flange portion thereof and effectively covers the impressed thread in the first two shells. This creates a double cap vappearance by completely concealing the threads on the inside shells or convolutely wound ribbon. The decoration, ornamentation Vor trade-mark illustration may be applied directly on the shell 8 either at the top thereof or on the surrounding Wall or both. which may be applied easily either before or after the formation of thisv finishing shell 8.

`If the additional top Wall structure is not required, indicated at l'l in Fig. 9, the finishing shell may be formed by a, convolutely Wound ribbon, shown at 9 in Fig. 8, applied directly over the shells l-Z and 4.

The structure of Fig. 8, including two shells and a surrounding convolutely wound paper ribbon, may be further covered for additional strength or ornamentation with a decorated or plain paper ribbon shown at l in Fig. 7, having an inturned flange ll folded over at the top `edge of the formed cap and covered by a decorated or plain disc i2, as shown in Fig. 7. Thus two or more shells may be used, or combination of shells and convolute Winding of paper ribbon, to form the finished cap, according to the strength and rigidity and decoration desired. The several shells or ribbon portions should be secured together effectively by means of adhesive or other suitable material that will form a substantial rigid structure, even though made up of relatively thin paper sections. By impressing one thread into apreceding thread groove, either by using multiple shells or convolutely Wound paper ribbon in combination With a shell or shells, a rigid thread is produced on the inside of the cap which has perfect stability'in resistingthe thrust of glass or other threads on containers, and which thread .thus formed is much more rigid with greater stability than ii formed by a single operation irnpressedv through the multiple thickness, thus formingr the surrounding Wall. This would not be possible if formed of cardboard or other heavyV paper.

The closures made heretofore have required a liner of suitabie material for sealing the contents of the container. By coating, if desired, the full shell on the inner side with a suitable material, indicated at l'l in Fig. 9, it is unnecessary to insert a liner therein, and this has the advantage of offering resisting surfaces on the side wall cap,

as Well as on the liner portion. This side wall protection is not possible with metal caps, except l second portion and into the first-mentioned smooth inner and outer surfaces, telescopng the thread groove.

A' 2. A process of making closure caps comprising forming a shell of relatively thin paper, with a top Wall portion and a surrounding vvall thereon, impressing Va thread groove in the periphery of said Wall, surrounding said Wall with a second Wall portion of relatively thin paper material, thereafter impressing a thread groove in said second portion and into the first-mentioned thread groove, and thereafter surrounding the second Wall portionwith a cylindrical cover that extends over the thread grooves and conceals the same.

3. A process of making closure caps comprising shaping a shell of relatively thin paper t0` form atop portion with a depending surrounding Wall, impressing a thread groove in the periphery of said wall to form a thread Within the cap, forming a second shell of relatively thin paper having a top and a depending surrounding wall with smoothinner and outer surfaces, telescoping the second shell over the first-mentioned shell, and impressing a thread groove in the wall of the secondshell and into the thread groove of the first-mentioned shell.

4. A process of making closure caps comprising shaping a shell of relatively thin paper to form a top portion With a depending surrounding wall, impressing a thread groove in the periphery of said wall to form a, thread Within the cap,y forming a second shell of relatively thin paper having'a top and a depending surrounding Wall with second shell over the first-mentioned shell, adhesively securing said shells directly together in permanent relation, impressing a thread groove in the periphery of the Wall of the second-mentioned shell and into the first-mentioned thread groove, and surrounding the Wall of the secondmentionedV shell with a covering extending over the thread groove and having a, smooth peripheral surface for concealing said thread groove.

5. Anprocess of making a closure cap comprising forming a shell from a sheet of relatively thin nonmetallic vmaterial by turning over the surrounding -edge to form a surrounding Wall on the top p'ortion of thel shell, thereafter impressing a thread groove iii-said surrounding wall, thereafter surrounding said wall and thread groove with a second Wall portion of thin non-metallic material, andimpressing a thread groove in the second wall portion after application to the first-mentioned Wall and into the mst-mentioned thread groove.

6. A process of makinga closure cap comprising forming a shell of relatively thin paper with a top wall portion and a surrounding wall thereon, impressing a thread groove in the periphery of said surrounding wall, surrounding said wall with a second wall portion `of relatively thin paper, thereafterimpressing a thread groove in thesec- 'ond Wall portion-and Tinto the Yiirst-rnenti'c'lnecl thread groove, and applying an end "ofv a paper p portion and winding said strip thereon to form a, Number convolute wall portion. 2,059,707 WILLLAM J. KEITH. 1,618,393 1,684,892 REFERENCES CITED 5 2,120,903 The following references are of record in the file of this patent. 9601226 UNITED STATES PATENTS Number Name Date 10 1,755,597 Greenewald xApr. 22, 1930 2,330,896 Keith oct. 5, 1943 Nuge'le 2,047,284 Morris July 14, 1936 Name Y n Date Robinson Nov. 3, 1936 Tevander Feb. 22, 1927 Sharp Sept, 18, 1928 Moore June 14, 1938 Shearman July 16, 1907 Fenn Feb. 12, 1907 Jenkins May 3:1, 1910 FOREIGN PATENTS Country Date England Nov. 1-8, 1929 

